Scaphoid Nonunion: Iliac Bone Graft with Herbert Bone Screw Fixation

Peter R. Carter, MD

The most common internal fixation technique used for hand fractures up to the mid-1980s employed the use of K-wires for simple fixation. Inspired by the fact that K-wires in themselves do not provide adequate stability for immobilization, Drs. Herbert and Fisher developed and subsequently reported (1984 JBJS) the successful use of a specially designed screw for the rigid fixation of scaphoid fractures and nonunions.

The titanium alloy screw is designed with both the differing diameter and incongruent thread pitch at the opposite ends. The incongruent thread pitch and differential diameters provide for compression of the fracture site upon screw insertion and eliminates the presence of a screw head which would interfere with joint articulation. An improved union rate has been achieved in the majority of clinical series employing the use of the Herbert bone screw. Most clinicians report that the Herbert screw has provided for increased stability and fracture immobilization resulting in earlier postoperative motion and return of function.

In the specific treatment of nonunions, the Russe bone graft technique has become a mainstay of treatment. However, in the treatment of avascular proximal pole segments, the modalities of treatment techniques remains varied. Dr. Peter Carter's experiences with the Herbert bone screw have provided him with a thorough understanding of the specific needs for treating scaphoid nonunions involving avascular proximal fragments. Dr. Carter asserts: "I feel very strongly that proximal pole fractures should be rigidly fixed immediately because from allograft patients we have good data now to show that with rigid fixation, a completely avascularized fragment (which the allograft most certainly is) can heal to an available piece of bone. In my opinion, I see that there is really no indication now to hold a proximal pole fracture in a plaster cast for an extended period of time to wait until the patient develops a nonunion which will most certainly occur."

In this VJO segment, Dr. Carter surgically demonstrates his iliac bone graft technique utilizing Herbert bone screw fixation for a chronic nonunion case complicated by an avascular proximal pole segment. In interview, Dr. Carter elaborates on the indications for scaphoid allografting; contraindications; electrical stimulation; the importance of leaving all of the wrist capsule that is attached to the lunate intact; the importance of iliac bone graft; and the changing beliefs regarding scaphoid fracture management for a variety of conditions.

Patient Information

22-year-old male who sustained a hyperextension injury to the wrist with 2-year-old fracture; nonunion/complete pseudarthrosis.

Early traumatic arthritis in the wrist and the beginnings of cyst formation in the borders of the nonunion and in the proximal pole.

Early degenerative changes at the dorsal lip of the lunate and slight increase in the scapholunate angle; however, not a markedly collapsed wrist.

The lunocapitate angle is also slightly increased and there is a tendency for the hand to sublux dorsally on the long axis of the forearm. References

Carter P Scaphoid Allografts Presented at the 42nd Annual Meeting of the American Society for Surgery of the Hand, San Antonio, Texas 1987

Herbert TJ, Fisher WE Management of the Fractured Scaphoid Using a New Bone Screw JBJS 66B:114-23, 1984